Long-term testosterone therapy does not increase risk of prostate cancer

Testosterone (T) therapy is routinely used in men with hypogonadism, a condition in which diminished function of the gonads occurs. Although there is no evidence that T therapy increases the risk of prostate cancer, there are still concerns and a paucity of long-term data.

In a new study in The Journal of Urology (2014; doi:10.1016/j.juro.2014.06.071), investigators examined three parallel, prospective, ongoing, cumulative registry studies of more than 1,000 men. Their analysis showed that long-term T therapy in hypogonadal men is safe and does not increase the risk of prostate cancer.

"Although considerable evidence exists indicating no relationship between testosterone and increased risk of developing prostate cancer, decades of physician training with the notion that testosterone is fuel for prostate cancer made it difficult to dispel such fallacy and the myth continued to persist, said lead investigator Ahmad Haider, MD, PhD, urologist, Bremerhaven, Germany.

“Nevertheless, in the absence of long-term follow-up data demonstrating reduced risk of prostate cancer in hypogonadal men who are receiving T therapy, considerable skepticism remains throughout the medical community and this is an expected natural and acceptable path of medical and scientific discourse. In view of the current evidence, clinicians are compelled to think this over and cannot justify withholding T therapy in hypogonadal men, also in men who have been successfully treated for prostate cancer."

A total of 1,023 patients on T therapy were followed for up to 17 years with a median follow-up of approximately 5 years. Two study cohorts of 261 (cohort 1) and 340 (cohort 2) men were treated by urologists since 2004 and a third cohort of 422 men was treated at an academic andrology center since 1996.

Hypogonadism was diagnosed if testosterone was 12 nmol/L or higher and if other symptoms were present, such as erectile dysfunction, fatigue, depression, or unfavorable changes in body composition (gaining of fat mass and waist circumference despite physical activity). If no contraindications were present, all were started on T therapy.

Cohort 1 had six (2.3%) diagnoses of prostate cancer, cohort 2 had five (1.5%) diagnoses of prostate cancer, and all biopsies were negative in cohort 3. Prostate cancer incidence per 10,000 patient-years in cohorts 1 and 2 was 54.4 and 30.7, respectively, which is lower than 116 reported by the PLCO (Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial) and 96.6 reported by the ERSPC (European Randomized Study of Screening for Prostate Cancer).

Investigators stress that if guidelines for T therapy are properly applied, it is safe in hypogonadal men.